Abstract
Emilie M.J. van Brummelen1,6, Marc C. Huisman2, Linda J. de Wit-van der Veen1, Tapan K. Nayak3, Marcel P.M. Stokkel1, Emma R. Mulder2, Otto S. Hoekstra2, Danielle J. Vugts2, Guus A.M.S. Van Dongen2, Henk M. Verheul2, Stefan Evers4, Jean J. L. Tessier3, Jose Saro4, Jan H.M. Schellens1,5 and C. Willemien Menke-van der Houven van Oordt2
1The Netherlands Cancer Institute, Amsterdam, The Netherlands
2VU University Medical Center/Cancer Centre, Amsterdam, The Netherlands
3Roche Pharma Research and Early Development, Roche Innovation Center, Basel, Switzerland
4Roche Pharma Research and Early Development, Roche Innovation Center, Zurich, Switzerland
5Utrecht Institute of Pharmaceutical Sciences (UIPS), Utrecht, The Netherlands
6Centre for Human Drug Research, Leiden, The Netherlands
Correspondence to:
C. Willemien Menke-van der Houven van Oordt, email: c.menke@vumc.nl
Keywords: immunocytokine; interleukin-2; 89Zr; biodistribution; immuno-PET
Received: March 24, 2018 Accepted: April 21, 2018 Published: May 15, 2018
ABSTRACT
Cergutuzumab amunaleukin (CEA-IL2v) is an immunocytokine directed against carcinoembryonic antigen (CEA) containing an IL2v-moiety with abolished IL-2 receptor (IL-2R) α binding. We describe the biodistribution and tumor accumulation of 89Zr-labeled CEA-IL2v. Twenty-four patients with advanced solid CEA positive (CEA+) or negative (CEA−) tumors received CEA-IL2v 6 mg (4 CEA+; 3 CEA−), 20 mg (9 CEA+), or 30 mg (4 CEA+; 4 CEA−) biweekly. In cycle 1, 2 mg of the total dose comprised 89Zr-CEA-IL2v (50 MBq) and serial 89Zr-PET imaging was conducted. Four CEA+ patients with visually confirmed 89Zr-CEA-IL2v tumor accumulation at 20 mg had repeated 89Zr-PET imaging during cycle 4. 89Zr-CEA-IL2v immuno-PET demonstrated preferential drug accumulation in CEA+ tumors (%ID/mLpeak CEA− 3.6 × 10−3 vs. CEA+ 6.7 ×∙10−3). There was a non-significant trend towards dose-dependent tumor uptake, with higher uptake at doses ≥20 mg. Biodistribution was dose- and CEA-independent with major accumulation in lymphoid tissue compatible with IL-2R binding. Reduced exposure and reduced tumor accumulation (%ID/mLpeak 57% lower) on cycle 4 vs. cycle 1 was consistent with peripheral expansion of immune cells. The findings of this immune PET imaging study with 89Zr-CEA-IL2v support the therapeutic concept of CEA-IL2v, confirming selective and targeted tumor accumulation with this novel immunocytokine.